Abstract
Between 1992 and 2017, the Antarctic Ice Sheet (AIS) lost ice equivalent to 7.6 ± 3.9 mm of sea level rise. AIS mass loss is mitigated by ice shelves that provide a buttress by regulating ice flow from tributary glaciers. However, ice-shelf stability is threatened by meltwater ponding, which may initiate, or reactivate preexisting, fractures, currently poorly understood processes. Here, through ground penetrating radar (GPR) analysis over a buried lake in the grounding zone of an East Antarctic ice shelf, we present the first field observations of a lake drainage event in Antarctica via vertical fractures. Concurrent with the lake drainage event, we observe a decrease in surface elevation and an increase in Sentinel-1 backscatter. Finally, we suggest that fractures that are initiated or reactivated by lake drainage events in a grounding zone will propagate with ice flow onto the ice shelf itself, where they may have implications for its stability.
Original language | English |
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Article number | e2020GL087970 |
Pages (from-to) | 1-9 |
Number of pages | 9 |
Journal | Geophysical Research Letters |
Volume | 47 |
Issue number | 15 |
DOIs | |
Publication status | Published - 2020 |
Keywords
- Antartica
- glaciology
- GPR
- hydrofracture
- hydrology
- meltwater